Process for the production of crude solder

Abstract

Disclosed is a pyrometallurgical process for producing a crude solder from a feedstock selected in terms of its levels of Sn, Cu, Sb, Bi, Zn, As, Ni and Pb, the process comprising at least the steps of obtaining in a furnace a liquid bath of metal and slag, introducing a reducing agent and optionally also energy, separating the crude solder from the slag and removing liquid from the furnace. Further disclosed is a crude solder comprising at least 9.5-69% wt of tin and at least 25% wt lead, at least 80% tin and lead together, 0.08-12% wt of copper, 0.15-7% wt of antimony, 0.012-1.5% wt of bismuth, 0.010-1.1% wt of zinc, at most 3% wt of arsenic, at most 2.8% wt of nickel, at most 0.7% wt of zinc, at most 7.5% wt of iron and at most 0.5% wt of aluminium. The crude solder may readily be further prepared to become suitable as feedstock for vacuum distillation.

The invention claimed is: 
     
       1. A crude solder comprising, in addition to unavoidable impurities and relative to the total dry weight of the crude solder:
 at least 9.5 wt % and at most 69 wt % of tin (Sn), 
 at least 25 wt % and less than 90 wt % of lead (Pb), 
 at least 80 wt % and at most 96 wt % of tin (Sn) and lead (Pb) together, 
 at least 3.5 wt % and at most 12 wt % of copper (Cu), 
 at least 0.15 wt % and at most 7 wt % of antimony (Sb), 
 at least 0.012 wt % and at most 1.5 wt % of bismuth (Bi), 
 at least 0.010 wt % and at most 1.1 wt % of sulphur(S), 
 at most 3 wt % of arsenic (As), 
 at most 0.10 wt % of Cr, Mn, V, Ti or W, 
 at most 2.8 wt % of nickel (Ni), 
 at most 0.7 wt % of zinc (Zn), 
 at least 0.0500 wt % and at most 7.5 wt % of iron (Fe), 
 at most 0.5 wt % of aluminium (Al). 
 
     
     
       2. The crude solder according to  claim 1  comprising at least 10 wt % of tin. 
     
     
       3. The crude solder according to  claim 1  comprising at most 68 wt % of tin. 
     
     
       4. The crude solder according to  claim 1  comprising at least 28 wt % of lead. 
     
     
       5. The crude solder according to  claim 1  comprising at most 85 wt % of lead. 
     
     
       6. The crude solder according to  claim 1  comprising at least 81 wt % of tin and lead together. 
     
     
       7. The crude solder according to  claim 1  comprising at least 4.0 wt % of copper. 
     
     
       8. The crude solder according to  claim 1 , comprising at most 10 wt % of copper. 
     
     
       9. The crude solder according to  claim 1 , comprising at most 0.69 wt % of zinc. 
     
     
       10. The crude solder according to  claim 1 , comprising at least 0.0001 wt % of zinc. 
     
     
       11. The crude solder according to  claim 1 , comprising at most 2.755 wt % of nickel. 
     
     
       12. The crude solder according  claim 1  comprising at least 0.050 wt % of nickel. 
     
     
       13. The crude solder according to  claim 1 , comprising at most 4.50 wt % antimony. 
     
     
       14. The crude solder according to  claim 1 , comprising at least 0.20 wt % of antimony. 
     
     
       15. The crude solder according to  claim 1 , comprising at most 7.00 wt % of iron. 
     
     
       16. The crude solder according to  claim 1 , comprising at least 0.1000 wt % of iron. 
     
     
       17. The crude solder according to  claim 1 , comprising at most 1.09 wt % of sulphur. 
     
     
       18. The crude solder according to  claim 1 , comprising at least 0.020 wt % of sulphur. 
     
     
       19. The crude solder according to  claim 1 , comprising at least 0.015 wt % of bismuth and at most 1.45 wt % of bismuth. 
     
     
       20. The crude solder according to  claim 1 , comprising at most 2.5 wt % of arsenic. 
     
     
       21. The crude solder according to  claim 1 , comprising at least 0.01 wt % of arsenic. 
     
     
       22. The crude solder according to  claim 1 , comprising at most 0.40 wt % of aluminium. 
     
     
       23. The crude solder according to  claim 1 , comprising at least 0.0010 wt % of aluminium.